Deleting history\app to get coupon more than once

hi hack forum friends.
I have a local application that gives coupon after a short game, the coupon has a unique number,
And I get a discount or a gift.
I'm trying to get the coupon more than once (after using the first coupon, get another one with a new number)
Deleting the app and reinstalling did not help and also delete History...... not help.
After reinstalling the app it writes"you already received a coupon" and not give me another one.
Im trying to access the software files and delete files completely\history how do i do it?
(I downloaded a "file manager" app to control files),
Can you help with that?